Heating system controlled by outside temperature



Oct. 9; 1951 2,570,810

' HEATING SYSTEM CONTROLLED BY OUTSIDE TEMPERATURE R. L. HOOGHKIR K f Filed March 11. 1947 2ND. FLOOR IST. FLOOR BASEMENT INVENTQR R.L .HOOGHKIRK ATTORNEY Patented Oct. 9, 1951 HEATING SYSTEM CONTROLLED BY OUTSIDE TEMPERATURE Richard L. Hooghkirk, Chicago, Ill., assignor to Iron Fireman Manufacturing Company, Portland, Oreg.

Application March 11, 1947, Serial No. 733,833

3 Claims.

My invention pertains to heating systems in general and more particularly to a heating system for a multiple occupancy building such as an apartment house or store building.

More specifically, my invention relates to the control of the heating system for a building and is particularly applicable to buildings where the use of fuel has been excessive and where it is desirable to limit the use of fuel to the essential heating requirements of the building.

In one form of my invention, a boiler in one isolated room of the building is used to supply heat to radiators located in other rooms of the building and the boiler is intermittently supplied with fuel by an electrically driven burner. My invention includes a control system for the electric drive of the burner whereby the interval between operations of the burner is governed by the outside temperature and whereby the end of any intermittent operation of the burner is determined by a limit control which has been located and set to operate when all of the radiators have been supplied with sufficient heat to heat the space in which they are located.

Another object of my invention is to provide a control for a heating system which is not only inexpensive to produce but is also inexpensive to install.

Other objects of my invention will become apparent upon a study of the following specifications referring to the attached diagrammatic drawing of one form of my complete system.

Referring nowto the drawing, there is shown a fragmentary section of a multiple occupancy building I with a boiler 3 in the basement. and radiators 2 in all rooms to be heated. A steam line 4 connects the boiler with all radiators and a return condensate line 5 connects all radiators with the boiler. The automatic fuel supply burner is shown at 6 and the electric motor operating the burner is l. A pressure limit control for the boiler is indicated as to location on the boiler at 8 while alternatetypes of limit controls that could be used with my system are shown as to location at 9 and Ill. If the limit control were located at position 9, it would be a temperature operated control operating in accordance with the temperature of the return condensate line. If the limit control were located at position I0 it would be a temperature control operating in accordance with the temperature of the hardest-to-heat radiator in the system. It is seen, therefore, that the limit control used to end an operation of my system could bechosen to fit the particular application in which it is used and could be any common limit control like a pressure control 8 on the boiler, a temperature 9 on the condensate line, or a temperature control H] on the farthest radiator. On the schematic wiring diagram of my control system there are shown alternate positions of the limit control. These positions are 13 and 24A. It is seen that any of the limit controls 8, 9 or ID could be used in positions l3 or 24 in my control circuit without affecting the operation of the circuit.

Proceeding now with a description of control circuit, we have electric power lines II and I2 supplying power to the burner motor 1 through elements H, l3, [8,1, [9, I5, l6, l1 and I2 where l5 and l! are stationary contacts on an electromagnetic switch and 1'6 is the bridging contact of the magnetic switch.

At I 4 is shown a transformer to reduce the power line voltage to the control circuit voltage. The primary of this transformer is fed through permanent attachment through lines l2 and I8. The operating coil 2| of the electromagnetic switch used to complete the burner motor circuit is fed from the secondary of the transformer l4 through line 2!] and line 25, 24A, 23 and 22 when ever the gap between lines 22 and 23 is bridged by any circuit closing means. Whenever the burner motor circuit is closed by the electromagnetic switch, the auxiliary contacts 24 and 25 of that switch are bridged by the bridging bar 26, therefore, whenever the electromagnetic switch is closed, the auxiliary contacts 24 and 25 being connected to lines 22 and 23 will maintain the electromagnetic switch in closed position until either the main supply circuit or the secondary control circuit is opened respectively by a limit control in position H3 or a limit control in position 24A.

It is understood that a burner operation could be initiated by any means desired and several means arehere shown. The simplest form of operation initiating means would be a momentary contact switch manually operated as indicated at 83 where the normally separated contacts of the switch are connected, one to line 22 and the other to line 23. Whenever these contacts touch each other,' current from the transformer It would energize the coil 2| of the electromagnetic switch, thereby closing the main and auxiliary contacts of the magnetic switch and thereby starting the motor and thereby also energizing the holding circuit which maintains the burner in operation. In my system, manually operated momentary contact switch 83 could be used as desired for a test switch or it could be omitted entirely. Also indicated on the drawing is a single pole double throw switch 35 which can be considered as the switching mechanism of a time operated program clock. The common point and blade 33 of this time switch is connected to line 22 and when the blade is switched to connect line 22 with contact 32, then a thermostat shown conventionally as 36 and SI could initiate an' operation of the burner since the blade 3! of the thermostat is connected to contact 32 of the time switch and the stationary contact 3% and the thermostat is connected to line 23. For purposes of illustration, we will call the thermostat 38, 3|, a night thermostat and another thermostat shown as 35', 3?, a day thermostat. The blade of this second thermostat 3": is connected to contact 31! of time switch 35 by line 22 and the stationary contact 35 is connected to line 23. When the blade 33 of time switch 55 connects with contact 3 3 the day thermostat can start an operation of the burner.

It is understood that the use of either a day thermostat or a night thermostat or both thermostats and a time clock is possible with my system but that they also may be omitted if desired.

At 82 is indicated a time delay mechanism which also is connected to lines 23 and 22 to initiate a burner operation and at El is indicated a thermostat which would preferably be located outdoors and which is used to control the amount of time delay elapsing before a new operation of the burner is to be initiated by the mechanismfif.

Returning now to the timing mechanism 52 we have a notched ratchet wheel 55 which can be rotated on a shaft 60- by either a movement of the ratchet arm 43 or a movement of the ratchet arm 49. Ratchet arm 43 is pivoted to fixed support 38 by a pin 45 and is yieldingly held in an upward position by spring 42 attached to ratchet arm43 at 46 and to fixed support 33 at id. A ratchet dog 44 is pivoted to ratchet arm is and on a downward motion of ratchet arm .3, dog 44 will engage ratchet wheel 55 and move ratchet wheel 56 in a right hand direction an angular distance equal to one notch on wheel 56. An electromagnetic operator is also connected to a ratchet arm d3 so that whenever the coil 55 of this operator is energized, ratchet arm 43 will be pulled downward and through dog 44 will operate ratchet 58 as above noted.

In asimilar way magnetic coil 54 through its armature attached to ratchet bar 49 and dog 48 will operate the ratchet wheel in a left hand direction whenever coil 54 is energized. Loose on shaft 60 and held in place against ratchet wheel 53 by a fractional spring nut 59 is a lever arm 58 haVi-ng a pin til at its outer end positioned to engage lever arm 62 when ratchet wheel 56 has advanced far enough in a clockwise direction. Pin 5? extends forwardly from ratchet wheel 56 to which it is firmly attached and will engage lever arm 62 when ratchet wheel 55 advances far enough in the counterclockwise direction. Lever arm 52 is pivoted at 63 and has firmly attached to it a spring conducting bar 54 which is attached by a flexible lead to wire 23. On one side of bar 5 are two contacts 6 and on the other side one contact 68, all of which are connected through the bar to wire 23. Stationary contact is connected to wire 22 and therefore, whenever contact 55-contacts with contact 66, wires 22 and 23 are connected and burner operation is initiated. Lever arm 62 is assumed to be so constructed as to be biased either in the right or left hand direction bystationary permanent magnets SI and 92 respectively so that it will not move from one of its contact positions until it will make a complete motion and will move to the other contact position. Permanent magnets 9| and 92 are positioned as shown to influence the magnetic armature 92 secured to lever 62.

At 8| is shown an outside thermostat having elements shown as a rigid insulating support 74 with an adjusting conducting screw 13 supported therein and also bimetal strip 15 anchored to support '54. Bimetal strip I5 is so placed as to move toward contact with screw 13 as it gets colder and to move away from contact 73 as it gets warmer. Adjacent to bimetal strip 15 is an electric heater 1? arranged to supply heat to bimetal l5 to urge bimetal 15 in a direction away from contact screw 13. One end of electric heater '57 is connected to bimetal strip 15 and also by wire it to one end of operating coil 55. The other end of electric heater i! is connected to line is electric resistor 19 contact 80 and line Eli-to the other end of operating coil 55. Ad justing screw i3is connected by line 12 to stationary contact 29 of a reverse acting auxiliary switch attached to the operator. of the electromagnetic switch which starts the motor. This reverse acting auxiliary switch has bridging bar 28 and second contact 2.'| which is connected by line-H to stationary contact 89.

One end of operating coil 54. is connected to line 25. The other end of operating coil 54 is connected by flexible lead 53 to a conducting bar as attached to ratchet lever arm 49. Bar has at its endcontact 5| which when lever arm-49 is held in the upward: position by spring 4 I, makes contact with stationary contact 52 supported on insulator 38 and connected to stationary contact 5? through wire 10.

It is seen that the ratchet timing mechanism 82 and the outdoor thermostat mechanism. 8| are actuated by power supplied by transformer it through lines 20 and 23. Thus when contacts 5S and 67 are closed, a power circuit is established between line 23; contact 55, 51, line it,- contacts 52, 5|, line 53, and operating'coil 5 1 to line 20 and coil 54 is energized thereby pulling lever arm 49 downward and operating the ratchet wheel one notch in the left hand direction. At the same time contacts 5|, 52 open this circuit, derenergizing coil 54, and ratchet arm 49 is again pulled upward by spring 4| and contacts 5| and 52 are again closed. This operation will repeat until ratchet wheel 56 has proceeded far enough in a reverse direction for pin 51 to contact lever 62 with suflicient force to throw lever 52 to. the right and thereby open contacts 65, 66, and El and close contacts-68 and 69. When contacts 58 and 69 are closed and if the burner is not in operation it is seen that a circuit is made from transformer l4 through line 23 to bar 64, contacts 68, 59, wire ii reverse auxiliary switch 27, 28, 29 line 72 adjusting screw 13 bimetal strip 75 to line 15. From line Hi there are two parallel paths which complete the circuit to line 20 and the other side of transformer I4. These two parallel paths are seen to be through operating coil 55 on the one hand, and through heater ll, line '58, adjusting resistor 19, 8B and line 2! on the other end. It is, therefore, seen that under these circumstances that when contact 58 and 59 are closed, operating coil 55 will be energized and heater T! will be energized at the same time. Because of this, ratchet arm 43 will be pulled downward and ratchet wheel 56 will be advanced one notch in the right hand direction and the as heater 1! has sufiiciently influenced bimetal strip to open the contact between bimetal 15 and screw 73. When the contact between screw 13 and bimetal 15 is broken bimetal strip l5will start to cool off and operating coil 55 will release ratchet arm 43 which under the influence of spring 42' willreturn toits upward position. When bimetal l5 has cooled sufliciently to again contact with screw 13 this operation will be again repeated until pin 6|- on arm 58- which travels with ratchet wheel 56 has rotated-far enough in the right hand direction to contact lever 62 with suflicient force to return it to the burner starting position of contacts 65 and 66. I

It should be noted that when the equipment is not supplying heat to the space to be heated, contacts 68, 69 of the stepping relay will be in engagement, and whenever blade 15 of remote condition responsive device 8| cools and contacts screw 13, stepping coil 55 and heater 11 will be energized and the stepping relay will 'make a step in the forward direction. Blade 15 will be quickly heated and open the 15, 13 contact, whereupon the stepping relay coil will be deenergized and ready for a new step when the i5, 13 contact is again closed. In the meantime blade 15 will cool slowly or quickly in proportion to the depression of the ambient temperature at that point and it is the cooling time after its quick heating which is the major timing period (variable) in the cycle of operation. The colder the ambient temperature the more rapid the cooling, the more frequent the cycling, and the more frequent the resulting cycling of the heat supply means.

Having thus illustrated in a schematic way the mechanism of my invention, I can describe the daily operation of my system as follows:

The time clock 35 can be set so that at some time in the early morning the switch blade 33 will be switched from contact 32 to contact 34 thus putting the control of my system under day thermostat 36, 31 and my outside timer mechanism 8| and 82. Day thermostat 35, 31 will be located somewhere in one of the spaces to be heated and will keep the burner in operation subject only to a limit control until the temperature of the building has been raised to a little less than that desired for day time operation. At the same time timer 82 and outside thermo stat 8| will start to measure out a time delay period before starting up the burner, each time the burner shuts down due to the operation of the limit control or due finally to the opening of day thermostat 36 and 31. Thus when day thermostat 35, 3! opens the control, the heating system goes over to the combination of the outside thermostat 8| and the timer 82. Repeated heating and cooling of thermostat BI and operating of actuating coil 55 causes pin 6| to throw lever arm 62 in a time which has been previously determined by the manual setting of arm 58 with respect to its position on ratchet wheel 56 which determines the number of notches which the wheel must advance before tripping lever 52. Also the length of time required to advance wheel 55 each notch is determined by the rapidity of cooling bimetal 15 which is determined by the outside temperature. Whenever the burner is started by the closing of contact 65, 65 the burner will be held in operation by auxiliary switch 24, 25 and 26 until the operation is stopped by a limit control. At the same time the contacts 65, 65 are closed contacts 66, 61 are closed and through 6 the operation above explained'the ratchet wheel is immediately-returned to its starting position where pin 51 has operated lever 62 to open contacts 65, 66 and 61 and close contacts 58 and'69. The time delay mechanism is then again ready to start another time delay timing period whenever the limit control opens the cicuit, operating coil 2| is de-energize'd and reverse auxiliary switch 21, 28 and "29 is closed.

Thus it is seen that as time switch 35 takes the control in the early morning from the night thermostat and transfers this control to the day thermostat and the outside timing control, the first operation is by the day thermostat which keeps the burner in operation limited only by the limit control until the space temperature is nearly upto the day temperature desired. At this time the day thermostat is satisfied and the combination of outside thermostat 8| and timer 82 carries on to bring the day temperature up to that desired. After the morning warm up period, it is seen that the complete control of the heating system is from the outside control to supply whatever heat is required in accordance with the outside temperature.

In the evening when the use of the building changes from average day use to average night use the setting of the time clock has been made so that the time clock switches blade 33 from contact 34 to contact 32, thereby taking control away from either the outside controller or the day thermostat and giving control to night thermostat 30, 3|. The night thermostat located in some part of the space to be heated will have a setting lower than the day thermostat in accordance with the usage of the building and will maintain in the space to be heated only this lower night temperature until the morning warm up period again starts in the morning.

It is, therefore, seen that I have provided a system giving a complete and desirable day round operation which results in sufficient burner operation to satisfy the requirements of the building but which limits the use of fuel to the standard requirements of the building for the particular weather being experienced.

Having thus completely described the construction of one form of the system of my invention and explained its operation, I claim:

1. The combination of means defining a space to be heated, means for heating said space, and electrical means for controlling said heating means, said electrical means comprising a power circuit for supplying power to said heating means, means for closing said power circuit and additional means for opening said power circuit, said circuit closing means including an aperiodic pulse delay means comprising manually operated means for setting the number of pulses to elapse before closing said circuit and means responsive to the outside temperature remote from said circuit closing means to control the time length of each pulse, said opening means including a limit control so pre-set and located as to initiate the opening of said circuit when a condition has been established whereby it is probable that heat has been supplied to all parts of the space to be heated.

2. The combination of means defining a space to be heated, means for heating said space, and electrical means for controlling said heating means, said electrical means comprising a power circuit for supplying power to said heating means, means for closing said power circuit, and additional means for opening said circuit, said closing means comprising a ratchet operated aperiodic delay meansa-nd. means responsive. to. the ambient temperature at a remote location to control said delay means whereby said power circuit is. closed wit-ha time. delay which varies as a function of. saidambient.temperature.

3.- The combinationv of an electric circuit to be closed, with a variabletime delay means for: closing said circuit, said delay means comprising. an aperiodic pulse: delay means having a manually operated means. for setting the number of pulses included in the time delay and means for controlling the timelength of. each. pulse cycle, said controlling means being responsive to the ambient temperature at a. location remote from said setting means. I

RICHARD- L. HOOGH-KIRK.

REFERENCES CITED The following, references are of record: in the file of. this patent.

UNITED STATES PATENTS Number Name Date.

1,604,342 Greenhut 0017.. 26, 1926 1,742,062 Day Dec. 31, 1929 1,883,735 Hall Oct. 18, 1932 1,925,781 Taylor Sept. 5, 1933 1,961,252 Shivers June 5, 1934 2,009,601 Anderson; July 30, 1935 2,030,542 Ross. Feb. 11,v 1936 2,171,147- Peltier Aug. 29, 1939 2,289,283 Brown n--. July '7, 1942 2436;735 Walder Feb..24-,.1948 

